This invention relates to rail mounted hot metal mixer vessels and more particularly, vessels of relatively large size.
In steel making plants, molten pig iron is commonly transferred from one or more blast furnaces to open hearth furnaces, oxygen converter vessels or other apparatus for further processing. In some plants, it is the practice to transport metal from blast furnaces by means of ladles whose contents are then poured into the open hearth furnace or converter as required. Another common practice is to pour metal from several heats of a blast furnace into a mixer vessel before charging into a metallurgical treatment vessel for further processing. As a result, it is possible to have a supply of molten pig iron on hand for charging to a converter vessel, for example, when necessary and also, the mixing of metal from several blast furnace batches is possible so that composition nonuniformities in different batches may be averaged.
One type of mixer vessel in common use comprises a transportable, elongate refractory lined cylindrical vessel suitably mounted for rotation about a longitudinal axis. Portability of the vessel is achieved by mounting its rotational bearings on spaced apart railroad type trucks with the vessel spanning the gap therebetween. The vessel is also provided with a pouring spout which permits the discharge of molten metal when the vessel is tilted.
While mobile type mixer vessels are relatively large, their size is nonetheless limited by factors relating to axle load capacity and the track gauge. For example, it will be appreciated that as the weight of the vessel increases, the number of axles must correspondingly increase so that the load bearing capacity of the individual axles are not exceeded. This increases overall vehicle length thereby creating handling and stability problems. Also, any increase in vessel diameter correspondingly raises the vehicle center of gravity thereby further contributing to instability problems particularly when traversing occurs.